The Difficulty of Forecasting Ambient Air Quality A Weak Link in Pollution Control

This article examines one important component of the problem of implementing the federal government's Clean Air policy, namely, the difficulty of quantifying the rela­ tionship between emissions to the atmosphere and ambient air quality. Short·, middle·, and long.tenn contt"ol strategies are discussed with an emphasis on the information needed for their effective assessment and implemeDlation. The reo quirement thus identified is compared with the information provided by air pollution models; it is shown that at theil" present stage of development, even the most sophisticated diffusion models are of limited usefulness in implementing CUl"rent llir pollution legislation. In view of the high cost of pollution control, further investment in model develop' mem is thought justifiable, though there al"e significant problems to be ovel"come. It is suggested that for the time being, panels of expel"ts might be used to make air quality fot·ecasts.